bromwich



C. M., sRGB/swam Lamp.

Patented Sept 2, 1862.

, No. I 36,337.

l'gg 2.

Psi/riesses:

UNITED STATES PATENT OFIQICE,v

c. M. BsoMw'oH, or Bos'romMAss.

DRAFT ATTACHMENT FOR LAMP BOXES.

Specification forming part of Letters Patent No. 36,33'7ydat'ed September 2, 1862.

To all whom it may concern:

Be it known that I, C. M. BRQMWICH, of Boston, in the county of Suffolk and State of Massachusetts, have invented a new and Improved Draft Attachment for Lamp-Boxes; and I do herebydeclare that the following is a full, clear, and exact description of the same, reference being had to the accom panying drawings, making a part of vthis specicatiom-in Which- Figure 1 is a centralsection of my invention, taken in the line v.fr Fig. 2, Fig. 2, a horizontal-section of the same, taken in the line y y, Fig. 1.

Similar letters of reference indicate corresponding parts in the two figures.. y

rlhis invention relates to an improved ar rangement for admitting of the escape of' airv from the lampfbox and the admission of the external air therein, whereby the .supply vof air to the dame of the lam-p is rendered uniform or constant and the flame allowed to burn without any flickering.

. The invention is more especially designed for coa1oil lamps, which requires. large amount of air in order to support proper combustion, and the dames of which are very sensitive or fasusceptible of being influenced by a slight A"change in the draft.

My invention 1s admirably well adapted for railroad-car and steamboat lamps, where the vibration attending the movement of said vehicles is liable to affect the flame as well as the fluctuation in the draft caused by the direct communication of the lamp-box with the external air. l

To enable those skilled in the art to full y understand` and construct my invention, I ,willproceed to describe it.

A represents a box, which may be of sheet metal and of rectangular or other form. This box is placed upon and secured to the box containing the lamp and communicates directly with it. On the upper part of box A there is placed another box, B, which commuy cates with A by means of an opening, a. The box B has a central elevated chamber', C, smaller in diameter than B, and which is encompassed by a box,.D, the lower end of which rests on the top of B, C projecting wholly upward in D and being' considerably smaller in diameter, as shown in both figures. The ele-v vated chamber C of the box B communicates with the box D by an opening, b, in its top, and the lower part of the box D is perforated all around, as shown at c. The upper end of the box D is closed, and is' also perforated 'all Y around, as shownat d, Fig. 1, and within said box D, just bellow the perforations d, there isv suspended a box, E, which .is somewhat in diameter than D, so as to admit of a space', e, all around between it and D, as shown in Fig. 1. y ,Y The box D, as well as ,the elevated lchamber Cof box B and the suspended box Ein D, may be of cylindrical form, while the boxesfAB may be of rectangular form; but I do not confine myself to any particular shape of any of the boxes.

The lamp-box below, in which the' .lamp is placed, is closed perfectly tight, no-air being allowed to`enter it at any point, and the box A, as previously stated, is secured to 'thetop of the lamp-box and communicatestherewifth; hence all the air'that enters the lamp-box' is from the top and th rough the device described. The warm air from the lampfbox passes up..- into box A, through the opening a into'box B, up into the elevated cham-ber. C, andthence through the opening b into box D, and is de? flected by the bottom of box E (which is perfectly tight and has no communication with D) to the sides of box D and passes out through the perforatons d. l (See black arrows.) The external cold air passes through the perforations c into lthe lower part of D, and passes upward to the top of C and'down through the opening b. through the, boxes Bv Aiuto the lamp-box, as'shown by the red arrows. The

warm air passes centrally up through the boxes, while the cold or fresh air passes down-` ward at 'the sides of the chamber Gand boxes B A, and when warmed and vitiated ascends,

its room being filled by the pure descending current. By. this arrangement the lamp-box is supplied with a stcadyuniform'draft or cur# rent of air, which is producedby the elevation of the box D above thetopof the chamber C. The warm air escaping 'at a higher point than that at` which the'pure cold air' en ters, a draft is induced through the openings or perforations c. ThisI feature of the invention constitutes its efficiency, for'if the eduction openings or pcrforations 'd were on a level with c there would be no dr'aft-at least not e Stiong and efcientne--to supply the 6eme with a requisite quantity of air. The suspended boX or deeetor E, in connection with the elevated chamber-1C, se1ves,.by giving a. clrcuitous route to the ascending and descending currents, to protect the draft from disturbmg causes without and render the draft more nmform than it otherwise would be.y

Having thus described my invention, what` I claim as new, anddesire to secure by Lettts The box B, provided withen elevated 

